Solar power is a gift from the sun. The energetic rays from the sun can be converted into both heat and electricity. The sun’s energy is a renewable source that is clean and free of pollution. One hour of sunshine produces more energy than what we globally consume in a whole year! We have only begun to scratch the surface for all the diverse uses of the sun’s energy. It can provide power for heating homes and water, running cars and computers and just about anything and everything we need. There is enough solar energy to fulfill all of mankind’s energy needs. The key is converting this power into a cost effective, usable energy in a big way.
How does solar power work?
Solar technology is based on either active or passive solar. Active solar power captures the sunlight energy and then converts it actively into either heat or electricity. Passive solar power simply traps the sun’s energy as in a greenhouse or passive solar home.
Solar collectors, or panels, are used to harness the sun’s energy. It is the solar cells within the panels that captures the energy. Thermal solar systems for heating the home are different from the photovoltaic systems used for generating electricity. Both involve solar panel collectors pointing at the sun either on the roof or free standing.
Solar thermal uses the energy of the sun to heat air or liquid. Most solar panels are a combination of fluid filled tubes and magnifying glasses. The special fluid in the dark tubes heats up quickly by both the direct intake of the sun through the glass front and further increased by a reflective surface behind the tubes. The heat produced in the tubes is then used to heat a tank of water. The hot water in the tank can now be used in the home or for radiant floor heating.
Photovoltaic (PV) solar systems use photovoltaic cells within the panels to convert the sun’s energy into electricity. This system is well suited to remote and rural locations since the PV cells require low maintenance. This technology involves using two different kinds of semiconductors whose electrons react with exposure to sunlight. It is this reaction that produces an electrical flow.
Solar energy options for the home
• One can design a passive solar home to specifically take full advantage of the sun for increased light and warming rays.
• One can install solar panels on the roof for converting sunshine into electricity.
• One can use roof mounted or separate solar panel collectors near the house to provide solar hot water heating.
Passive solar homes are designed to face south with large windows that allow for a flood of warm sunlight. If enough sunshine occurs daily, the passive solar gain is enough to warm a house with no other heat source. The solar gain is further increased with the use of poured concrete, stone or tile floors which effectively heat up during the day, and then release this heat slowly during the night. A thermal wall built to collect ample sunshine will provide another source of released heat. The use of insulated curtains or shades over the windows at night will trap the heat inside the house. In the summer time, an excess of heat can be regulated by the use of shade screens, landscaping, overhangs and good ventilation.
Solar electricity is created by the use of photovoltaic systems. This requires solar panels to be installed on a south facing roof, or can be installed as tracking panels to follow the sun if there is no direct southern roof exposure. These solar panels also have the option of being connected to the grid or not. If connected to the utility grid, you will begin to see a decrease in your electric bill. In some cases, you may even eliminate your electric bill completely and find the utility company paying you instead. If your system is not tied to the utility grid, it will be necessary to have alternative backup heat when gray days prevail. Some options are to charge batteries or use a generator. The biggest deterrent for the use of photovoltaics in the past has been their high cost, and the time it takes to recoup a return on such an investment. Government rebates and incentives come and go, but the more people demand these for the use of solar power, the more they will be made consistently available to the public. More solar companies are now offering finance programs to assist the move toward renewable energy.
Solar hot water heating, also referred to as solar thermal systems, collects the heat from the sun into storage tanks. Solar panel collectors can either be placed on the roof, or installed free standing near the home in an open southern exposure. These collectors are filled with small tubes that heat up, then transfer and deposit the warm liquid into the insulated storage tanks. These holding tanks offer the advantage of working well despite minimal sunshine so they are optimal for many locations and climates. My favorite heating system is radiant floor heat, and solar thermal systems are ideal for this, as well as for heating swimming pools.
We are long overdue in America for converting our lifestyle towards renewable energy. How much longer will we choose to tolerate escalating fuel costs, health threatening air pollution, depletion of our planet’s resources and global warming before we make this change? Our choices make no sense when the possibility for clean air, free energy and harmony with nature are at our fingertips.